My 1990 Si hatch feels like it has a 40hp gain over my other 1991 Si hatch. Here are the specs of both cars. 1990 Si: -Stock to the bone. -1989 Si 5 speed tranny because it used to be an automatic. 1991 Si: -Mini-Me (D16A6 block, D16Z6 head). -Its not tuned yet. -Its on a 1988 DX 5 speed tranny. -Short ram intake. -Restricted exhaust (small diameter) -D16A6 head gasket (thicker than the D16Z6 one) -DX D15B2 exhaust manifold (if it makes a difference) Both cars are the same weight and both cars have the same compression. In a drag race I'd bet $1000 for the 1990 winning. The 1990 is also so much more responsive in the lower RPMs. Do you think when I get a D16Z6 headgasket on, the Si tranny, a Si header (if its different than a DX one) and get it tuned it will kick my 1990's ass?